Placeholder text (also referred to as variable text or replaceable text)
stands for an object whose specific name is unknown to us. Placeholders
are included when documenting syntax for how a command or path should be
constructed. Users supply the relevant value for the placeholder
when using the command or syntax.

Placeholder text usually indicates the type of element that's being
represented. For example, directoryName would likely indicate the name
of a directory.

Note

Placeholder text is distinct from environment variables.
Environment variables have established formats and names, such as
$account, and their values are set in the system by users and
used consistently. By contrast, a placeholder is given a relevant value
by the user at the time that the user runs the code or types the
path. For information about formatting environment variables, see
Text formatting.

When creating placeholder text, use the following guidelines.

Note

For specific information about showing placeholders for
account information such as account numbers, usernames, passwords, and
API keys, see Cloud account information.

Guidelines

Example

Within regular text, show placeholder text in italics.

Within code samples, use the RST :samp: directive, and enclose the
placeholder text in curly braces. This formatting renders the
placeholder in italics.

If you can't apply text formatting to the code, enclose placeholders in
punctuation that doesn't have any other special use in the code. For
example, use angle brackets or curly braces. Use a consistent convention
throughout the documentation set.

novabootserverName--imageimage--flavorflavor--nicnet-id=net1_id

Use lowercase letters except when showing a multiple-word placeholder.

To show a multiple-word placeholder, don't separate the words with
spaces or symbols. To distinguish the words in the placeholder,
capitalize the first letter of each word after the first word (called
camelCase). Don't capitalize the first word.

Note: Use lowercase and camelCase unless you have to follow the
conventions of the programming language. For example, you might need
to use underscores (account_ID) or all capitals (ACCOUNT_ID).

passwordserverNameapiKeytenantId

In general, use one or more whole words to represent a placeholder.
Don't sacrifice clarity for brevity. Create placeholders that are
descriptive and meaningful.

device (instead of dev)

installationDirectory (instead of installDir)

mode (instead of ########)

When explaining a placeholder, use the following guidelines.

Guidelines

Example

Avoid stand-alone clauses that begin with where. Instead, use a
sentence.

Use:

https://dfw.bigdata.api.rackspacecloud.com/v1.0/yourAccountId/

yourAccountId is your actual account number, which is returned as part
of the authentication service response.

Avoid:

https://dfw.bigdata.api.rackspacecloud.com/v1.0/yourAccountId/

where yourAccountId is your actual account number, which is returned
as part of the authentication service response.

If you need to explain two or more placeholders, use an unordered list.

From a supported web browser, type the following URL:

http://hostName:portNumber/ed/index.html

The placeholders in the URL are defined as follows:

hostName is the name of the host computer on which the application
server is installed.

portNumber is the port number assigned to the application server.
The default is 8082.

Show the placeholder in regular text with the same formatting that it's
shown in the path or code. For example, if you can show it in italics,
use italics when explaining it. If you first show the placeholder in a
code block and need to enclose it in angle brackets, show it in angle
brackets and monospace when explaining it.

Use:

https://dfw.bigdata.api.rackspacecloud.com/v1.0/yourAccountId/

yourAccountId is your actual account number, which is returned as part
of the authentication service response.

Use:

Run the following command, replacing <dockerHostName> with the name
of your Docker host: